J/ApJ/761/143 Black hole masses of z∼1.4 AGNs from SXDS (Nobuta+, 2012)
Black hole mass and Eddington ratio distribution functions of X-ray-selected
broad-line AGNs at z ∼ 1.4 in the Subaru XMM-Newton Deep field.
Nobuta K., Akiyama M., Ueda Y., Watson M.G., Silverman J., Hiroi K.,
Ohta K., Iwamuro F., Yabe K., Tamura N., Moritani Y., Sumiyoshi M.,
Takato N., Kimura M., Maihara T., Dalton G., Lewis I., Bonfield D., Lee H.,
Curtis-Lake E., Macaulay E., Clarke F., Sekiguchi K., Simpson C., Croom S.,
Ouchi M., Hanami H., Yamada T.
<Astrophys. J., 761, 143 (2012)>
=2012ApJ...761..143N 2012ApJ...761..143N
ADC_Keywords: Active gal. nuclei ; X-ray sources ; Redshifts ; Infrared sources
Keywords: galaxies: active; galaxies: evolution; galaxies: statistics;
quasars: emission lines; quasars: general
Abstract:
In order to investigate the growth of supermassive black holes
(SMBHs), we construct the black hole mass function (BHMF) and
Eddington ratio distribution function (ERDF) of X-ray-selected
broad-line active galactic nuclei (AGNs) at z∼1.4 in the Subaru
XMM-Newton Deep Survey (SXDS) field. A significant part of the
accretion growth of SMBHs is thought to take place in this redshift
range. Black hole masses of X-ray-selected broad-line AGNs are
estimated using the width of the broad MgII line and 3000Å
monochromatic luminosity. We supplement the MgII FWHM values with the
Hα FWHM obtained from our NIR spectroscopic survey. Using the
black hole masses of broad-line AGNs at redshifts between 1.18 and
1.68, the binned broad-line AGN BHMFs and ERDFs are calculated using
the Vmax method. To properly account for selection effects that
impact the binned estimates, we derive the corrected broad-line AGN
BHMFs and ERDFs by applying the maximum likelihood method, assuming
that the ERDF is constant regardless of the black hole mass. We do not
correct for the non-negligible uncertainties in virial BH mass
estimates. If we compare the corrected broad-line AGN BHMF with that
in the local universe, then the corrected BHMF at z=1.4 has a higher
number density above 108M☉ but a lower number density below
that mass range. The evolution may be indicative of a downsizing trend
of accretion activity among the SMBH population. The evolution of
broad-line AGN ERDFs from z=1.4 to 0 indicates that the fraction of
broad-line AGNs with accretion rates close to the Eddington limit is
higher at higher redshifts.
Description:
A sample of z∼1.4 AGNs is constructed from X-ray observations of the
SXDS field (Ueda et al. 2008, Cat. J/ApJS/179/124). In this paper,
only X-ray sources in the region covered with deep optical imaging
data taken with Suprime-Cam on the Subaru telescope (Furusawa et al.
2008, Cat. J/ApJS/176/1) are considered.
In order to identify the X-ray sources spectroscopically, optical
observations were conducted with various multi-object spectrographs on
4m and 8m class telescopes. Details of the observations are summarized
in M. Akiyama et al. (2012, in preparation).
Additional intensive NIR spectroscopic observations were made with the
Fiber Multi-Object Spectrograph (FMOS) on the Subaru telescope. The
spectrographs cover the wavelength range between 9000Å and
18000Å with a spectral resolution of R∼800 at λ∼1.55um in
low-resolution mode.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 67 215 Broad-line fitting results for the broad-line AGNs
table4.dat 26 215 Black hole mass and λEdd of broad-line AGNs
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See also:
B/xmm : XMM-Newton Observation Log (XMM-Newton Science Operation Center, 2012)
B/subaru : Log of Subaru Prime Focus Camera Exposures (ADAC NAOJ, 2007)
J/A+A/549/A119 : Black-hole masses of type-1 AGNs (Caccianiga+, 2013)
J/MNRAS/423/600 : Type-1 low-z AGN emission properties (Stern+, 2012)
J/MNRAS/421/3060 : Subaru/XMM Deep Field radio imaging. III. (Simpson+, 2012)
J/ApJ/753/125 : NIR spectroscopy follow-up of 60 SDSS-DR7 QSOs (Shen+, 2012)
J/ApJ/746/169 : Luminosity function of broad-line quasars (Shen+, 2012)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/ApJS/194/42 : SDSS-DR3 MgII-based black hole masses (Rafiee+, 2011)
J/ApJS/189/270 : MUSYC optical imaging in ECDF-S (Cardamone+, 2010)
J/ApJS/187/560 : Photometric redshifts of the 2Ms CDF-S (Luo+, 2010)
J/ApJ/716/348 : The XMM-Newton survey of the COSMOS field (Brusa+, 2010)
J/ApJ/699/800 : Mass functions of active black holes (Vestergaard+, 2009)
J/ApJ/690/20 : Models of AGN and black hole populations (Shankar+, 2009)
J/ApJS/176/301 : Subaru/XMM-Newton deep survey IV. (SXDS) (Ouchi+, 2008)
J/ApJS/179/124 : Subaru/XMM-Newton deep survey (SXDS) III. (Ueda+, 2008)
J/ApJS/176/1 : Subaru/XMM-Newton deep survey (SXDS). II. (Furusawa+, 2008)
J/ApJ/688/826 : Radio and X-ray-emitting broad-line AGNs (Li+, 2008)
J/ApJ/680/169 : SDSS DR5 virial black hole masses (Shen+, 2008)
J/AJ/135/928 : The black hole-bulge relationship (Shen+, 2008)
J/ApJ/670/92 : New sample of low-mass black holes in AGN (Greene+, 2007)
J/ApJ/669/791 : Quasar black hole masses (Wilhite+, 2007)
J/ApJ/667/131 : Mass function of active black holes (Greene+, 2007)
J/ApJS/168/1 : Black hole mass estimates (Kelly+, 2007)
J/ApJS/166/470 : SDSS-Spitzer type I QSOs IR photometry (Richards+, 2006)
J/ApJ/634/861 : Old passively evolving galaxies at z=1 (Yamada+, 2005)
J/ApJ/613/682 : AGN central masses & broad-line regions (Peterson+, 2004)
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [10/1242] Source identification number;
<[UWS2008] NNNN> in Simbad
6- 10 F5.3 --- z [0.4/2.4] Redshift
12- 16 F5.2 [10-7W] logLXh Log of 2-10 keV hard X-ray luminosity; erg/s
18- 22 I5 km/s W(Mg) ? FWHM of broad MgII emission line
24- 27 I4 km/s e_W(Mg) ? Uncertainty in W(Mg)
29- 39 A11 --- n_W(Mg) MgII line model used (1)
41- 45 I5 km/s W(Ha) [1492/11056]? FWHM of broad Hα emission
line
47- 49 I3 km/s e_W(Ha) [3/456]? Uncertainty in HaWidth
51- 55 A5 --- n_W(Ha) Hα line model used (1)
57- 61 F5.2 [10-7W] logLo Log of 300nm (3000Å) monochromatic
luminosity; erg/s (2)
63- 67 F5.2 mag R-i [-0.4/1] The (R-i) color index
--------------------------------------------------------------------------------
Note (1): Model as follows:
OneBL = one broad line;
TwoBL = two broad lines;
ThreeBL = three broad lines;
OneBLOneAbs = One broad and one absorption line;
OneBLTwoAbs = One broad and two absorption lines;
TwoBLOneAbs = Two broad and one absorption lines;
TwoBLTwoAbs = Two broad and two absorption lines;
BLNL = one broad line + narrow emission lines.
Note (2): For a part of the objects, the 3000 Angstrom monochromatic
luminosity is derived from the 2-10keV hard X-ray luminosity.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- ID [10/1242] Source identification number;
<[UWS2008] NNNN> in Simbad
6- 10 F5.3 --- z [0.4/2.4] Redshift
12- 14 F3.1 [Msun] logM [6.6/9.8] Log of the black hole mass
16- 20 F5.2 [10-7W] logL [43/48.1] Log of the bolometric luminosity;
in erg/s (3)
22- 26 F5.2 [-] logWEd [-2.5/0.2] Log ratio of observed and
Eddington-limited accretion rates
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Note (3): From the 3000Å monochromatic luminosity and using a bolometric
correction factor of 5.8 for the monochromatic luminosity from
Richards et al. (2006, J/ApJS/166/470), following Vestergaard & Osmer
(2009, J/ApJ/699/800). For a part of the objects, the 3000Å
monochromatic luminosity is derived from the 2-10keV hard X-ray
luminosity.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 14-Aug-2014